If $x \barwedge y = x(y-7)$ and $x \star y = 4x-5$, find $1 \star (-5 \barwedge 5)$.
Solution: We don't need to find $-5 \barwedge 5$ because $x \star y$ depends only on the left operand. Find $1 \star y$ $ 1 \star y = (4)(1)-5$ $ \hphantom{1 \star y} = -1$.